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hoofvet
01-31-2005, 09:26 PM
I have been a farrier/blacksmith for about 19 years, and am quite proficient in what I do. But, when it comes to machining I seem to be quite lost. More specifically my problem right now is as follows: I just recently bought as mini-lathe and just started trying to work with it tonight. My problem is that I am not sure how the various bits are actually supposed to be securely mounted. This is an 8" x 12" lathe from Harbour Freight ( have to start somewhere for those who don't like HF). I know where the bits go, etc. But, for instance I have a 1/4" square bit, Am I missing something to place it in and then secure it to the tool rest?? This is probably very obvious, but I am starting from ground zero. Any help or direction to good books would be GREATLY appreciated.

Thanks,
Jonathan Cohen DVM

Boogiemanz1
01-31-2005, 10:18 PM
Hi Jonathan, Welcome to MetalMeet.

I think you are referring to the turning tool. Usually they are secured to the toolholder on the cross slide. The toolholder should have a handle on top to loosen it so it can be positioned, and screws along the sides to tighten the tool in with.

There are several sites in the net that specialize in those small lathes. This link is to one one of themhttp://www.mini-lathe.com/Mini_lathe/Features/features.htm..............john

Kerry Pinkerton
02-01-2005, 04:56 AM
Welcome Jonathon,

If you don't have the manual, you can download it from the Harbor Freight web site free.

Click here:

http://www.harborfreight.com/cpi/ctaf/Displayitem.taf?itemnumber=44859

and at the bottom of the page is the download product manual button. Sometimes they are good...sometimes not.

Matt Ferrari
02-01-2005, 06:40 AM
Welcome, Jonathan.

You may not have the right toolholder for your lathe. I'm not sure.

Here's a great resource for information on how to use the mini-lathe, including some videos and additional tools:
http://www.littlemachineshop.com/

I hope that helps a little.

--Matt

hoofvet
02-01-2005, 09:49 PM
Thanks for the fast responses and help!!!
I had one other question along the same line. I got with the lathe what are supposed to be quick change bit holders. Is anybody familiar with them, and how they are to mount. Do I need to completely remove the OE tool rest or do they attach somehow??
Thanks Again!

CCWKen
02-01-2005, 10:33 PM
It sounds like you're missing the quick change tool post. It mounts in place of the stock "4-way" post and will have a lever to release the "tool holder". That's what makes the QC tool post so nice. You normally have 5 or more tool holders set up with different bits or tools. I know a few guys that have 20+ holders!

1/4" sounds small for that lathe. If you mount bit in the stock tool post, you have to make sure the cutting edge is even with the center line of stock (For normal turning). You either put the bit in a tool holder or shim it up. The QC tool holders are adjustable. That's why you use more holders. You adjust the holder once for the bit or tool that's in it and leave it. From then on, it's just a matter of swapping holders--Quick Change.

Renee n Jerry Conrad
02-03-2005, 05:26 PM
Hi Jonathan,
Lindsay Publications (www.lindsaybks.com) sells a lot of metalworking resource books. I believe the best in the field is "How to Run a Lathe 1942" by South Bend Lathe Works. Lindsay's no 21150, $7.95. Good bookstore. This is a recognized best basic course in basic lathe operation. They tell you how and why.
Good Luck!
Jerry Conrad

captainkirk
02-04-2005, 03:41 AM
I agree with the suggestion to get the book "How to Run a Lathe" it is very short and very well written for someone starting out with a new lathe.
One word of caution if you havn't hit it yet, most people without any lathe background make a very common mistake when turning they dial in say .003 with the thought that they want to remove that amount from the object. This will in fact remove .006 from the diameter. I say this because it is a common mistake when starting, to cut the basic rule is to measure what your current diameter of stock is and then deduct the desired diameter from that reading take this figure and divide it in half that is going to be your "tool bit feed in amount". Another note don't try and finish with a really small cut last as this usually causes the bit to ride in and out of the work causing a rough surface finish, this is a worse problem with the small light lathes as they lack rigidity and tend to like a finish cut in the .003 (total .006) range also I suggest using HSS tooling as you get started your likely to have better results with surface finish.
That lathe as it arrives will likely need "some adjustment" to function without some major frustration, if things are not working out for you don't make the assumption your doing it wrong those lathes can be made to do some really nice work, but it take someone that knows how to "tune them up" to get the best from them. I wish they sent them all in pieces that way people wouldn't expect them to work when they are pulled from the box. I live in Warrenton Va. if I can be of some help or if you want to bring it over I can give you some pointers and help to set it up to start contact me off list at capt.kirk@erols.com or 540-349-7113 I'll be glad to help, I know the frustration of starting out without a good base of knowledge

kenklose
02-04-2005, 08:43 AM
I'm learning machining and I agree "How to Run a Lathe" is an excellent book. Lindsay also prints a few project books by South Bend that look pretty good (I've only skimmed them).

My question: does anyone know of an equivalent good book for learning to run a Bridgeport type mill?

Renee n Jerry Conrad
02-04-2005, 06:19 PM
Hi Ken,
The Home Shop Machinist magazine, Villiage Press, Inc. http://www.homeshopmachinist.net/ has videotapes by Rudy Kouhoupt www.bay-com.com. 2 hour video "Fundamentals of Milling Machine Operation for $53.95. Havn't seen it but I've read this guys articles for 30 years and he's good!
www.mastermachinsitvideos.com has 90 minute "Tape1" "Milling Machine", $34.95 + $4.95 shipping.
The only worthwhile book I've found is comprehensive of machining operations and is pricey at $47.50. Machining Fundamentals by John R. Walker. This is a vocational school textbook and is available from Villiage Press Publications or www.lindsaybks.com This covers the entire machining field, but is not as hands-on as South Bends book.
You might try www.half.com, www.ebay.com and www.amazon.com for better prices? We've done well at used book shops and the local Goodwill too.
Hope this helps,
Jerry

Don Thorne
02-11-2005, 12:42 PM
Help!!! :arrow: This week-end I’m going to be turning, on my lathe, a 5 inch diameter piece of what looks like UHMW or Delran.

My question is at what speed (RPM) should I turn to get the best quality cut? Also is there a special shape the cutting bit should be? I’ll be cutting from ½” to the full 5” range. :?:

Thanks in advance and any feed back will be welcome.

Don

hoofvet
02-12-2005, 09:10 PM
The first time I used my lathe it centered some round bar stock no problem. Ever since then I have had great difficulty getting the same stock centered so that it spins true. Any ideas what I could have screwed up?? This is a three jaw chuck.

I appreciate any help and advice. Thanks again!
Jonathan Cohen

ralph
02-14-2005, 06:46 AM
Johnathan,

You've just learned one of the weakness of three jaw chucks. All three jaws chucks have some radial runout. It shouldn't be worse than .002-4". Whenever its necessary to remove a part between operations, mark the part in reference to one of the jaws so you get the same registration when you put it back. Also, try and come up with a repeatable jaw tightening sequence.

Gene_Olson
02-14-2005, 07:21 AM
one thing that helps is to set one of the jaws at the bottom when you put the part in;

then it sits balanced there on the jaw and the other two jaws nudge it to center.

If you try and tighten in any other position the part will fall between the jaws and be off center.

G

Avalonjr
08-26-2005, 06:20 AM
I'm also new to turning operations. My lathe doesn't have a feed screw on the compound and I don't have a taper attachement.

Can anyone describe the proper method to radius an edge or add a taper?

Timmy_k
08-26-2005, 09:24 AM
Hey Don,

I have always had good luck turning UHMW @ 400-500rpm. Your bits need to be razor sharp. Any higher revs and you will get a thread like rats nest.

tim k